Radiation hardening of circuit components is a major concern where such circuits have a critical function.
Tremendous strides have been made in the field of semiconductors for making components radiation hard, that is, circuits which may be impervious to electromagnetic radiation from gamma and x-rays. However, photosensitive circuits and photodetector components have a problem unlike other components since they must be responsive to electromagnetic radiation in the form of visible light, or other selected portion of the frequency spectrum.